Trudy â€” Rd No 711837 is a glass registration by International Bottle Co. Ltd. on March 19, 1925, according to Jim Edgley's "Blue Book", published by the Glass Association, and obtainable from Broadfield House Glass Museum.
In my opinion most International Bottle Co. Ltd. glass was made in continental Europe. I believe they were factors, supplying the retail trade rather than selling directly to the public, with experienced design, sales and marketing teams, putting manufacturing out to tender and going for the best deal. They produced some classy Art Deco glass in the 1930s which looks very French or Czechoslovakian â€” see Miller's Glass Buyer's Guide
for two or three illustrated examples.
Note that if you find contemporary references to them as "manufacturers", this does not necessarily mean that they made the glass, but that they arranged for it to be made. It is our use of the word manufacture
that has changed â€” now it means to make or to assemble or a combination of the two, at least here in Britain â€” it may have changed less in meaning in the USA, where the English language is rather more stable.
Oh, and excellent title for this topic. :clap: